My 2 cents:
I use software that does the job. OpenSource is not necessarly free, just
means one can get the sources and compile it, twiddle the code, if one so
chooses. Not all musicians can or want to bother with this. One thing is that
opensource authors are much more accessible and listen to suggestions. This
has made nted into quite an effective scoring package. Put down top bucks for
Sibelius, great program but you buy the package, that's it.
Two big windows DAWs, Sonar and Cubase are costly but get the job done quite
nicely. Why would one want more? Same goes for Protools on the Mac (I found
the windows port awful). A few "smaller" choices are around and serve well
folks that prefer them. I used Sonar's little sister, Home Studio, more bang
for the buck, until the upgrade demanded newer windows. Then my windows 98!
died, ending that. Did nice work with this program and if it would run on
wine, I would continue with it, even the old version. Good old Cakewalk
"Express" runs on wine but is restricted to two audio tracks. Could even live
with that, keeping the MIDI as MIDI, but ...
I still use Jammer which runs nearly 100% on wine and Style Enhancer which is
OK on wine as well. XGedit for the XG sound generator (no ALSA driver, but can
be used as an MPU401) also 100%. I have not chosen a DAW yet for Linux.
OOMidi2 looks a lot like Home Studio, same drawn automation model. Qtractor
looks quite good as well. Rosegarden is a mature, well developed software.
Ardour3 with MIDI will be a solid contender and there is a luscious paid
version around (Ardour 2 based right now) which I might consider buying. Count
them, and I have not even mentioned all of them. Linux and Opensource are
about choice. I would still put down bucks on a top-flight software based on
opensource (or even something excelent though proprietory). The one fly in the
ointment of all this choice as lack of interoperability that would let me use
several of these programs as desired, but one cannot do this on high-ticket
proprietary windows or mac stuff either.
Most all the DAWs support/need plugins and many the wealth of free and paid
VSTs can be used in the programs in addition to the Linux native formats. I
need registration codes for the "new" computer/OS for some of these but I have
worked miracles with them, so ...
There is nothing wrong with using, continuing to use windows or macs for
audio. Keep paying for upgrades when the upgrades (even free) for the software
require the newer windows or OSX. Maybe worth the cost. Most of the gear costs
much more.
But I would love to finally get a full project off on the Linux/opensource
packages even if I start out with wined windows tools for MIDI (these tools do
what I want--they are getting quite old, and I have suggested that their
authors release them to opensource some time along the road. I beta'ed and
worked with these folks so maybe have some influence).
Now with all the alternatives simply, choose, start singing and mixing.